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bioRxiv · 10.1101/2024.06.01.596487

Human motion data expansion from arbitrary sparsesensors with shallow recurrent decoders

Ebers, M. R.·Pitts, M.·Steele, K. M.·Kutz, J. N.
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Abstract

Advances in deep learning and sparse sensing have emerged as powerful tools for monitoring human motion in natural environments. We develop a deep learning architecture, constructed from a shallow recurrent decoder network, that expands human motion data by mapping a limited (sparse) number of sensors to a comprehensive (dense) configuration, thereby inferring the motion of unmonitored body segments. Even with a single sensor, we reconstruct the comprehensive set of time series measurements, which are important for tracking and informing movement-related health and performance outcomes. Notably, this mapping leverages sensor time histories to inform the transformation from sparse to dense sensor configurations. We apply this mapping architecture to a variety of datasets, including controlled movement tasks, gait pattern exploration, and free-moving environments. Additionally, this mapping can be subject-specific (based on an individuals unique data for deployment at home and in the community) or group-based (where data from a large group are used to learn a general movement model and predict outcomes for unknown subjects). By expanding our datasets to unmeasured or unavailable quantities, this work can impact clinical trials, robotic/device control, and human performance by improving the accuracy and availability of digital biomarker estimates.

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Ebers, M. R., Pitts, M., Steele, K. M., Kutz, J. N.. 2024-06-03. Human motion data expansion from arbitrary sparsesensors with shallow recurrent decoders. https://doi.org/10.1101/2024.06.01.596487

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